Evaluate the following expression when $x = 6$ and $y = 6$. $10$ $x$ $ + 8$ $y$ $ + 7$
Solution: Substitute $6$ for ${x}$ and $6$ for ${y}$ $ = 10{(6)} + 8{(6)} + 7 $ $ = 60 + 48 + 7 $ $ = 115$